己二醛可用于聚酰胺(如尼龙-6,6)、聚酯和聚氨酯等的制备,然而,其化学合成面临着高成本、不易循环、对环境不友好等一系列挑战。为了开发绿色的己二醛合成工艺,该研究利用己二酸为原料构建己二醛生物合成途径,通过基因敲除和发酵优化提高生产效率,最后通过体外催化降低产物毒性抑制以提高己二醛积累量。结果表明,敲除部分内源性醛还原酶基因以及进行发酵优化可显著提高产量,己二醛的发酵产量较初始菌株提高了20.3倍,达到190 mg/L。在此基础上进行体外催化,其产量较初始菌株提高了32.2倍,达到295.8 mg/L,是目前己二醛生物合成领域的最高报道。该研究可为脂肪族二醛的生物合成提供支持和借鉴。
1,6-Hexanedial serves as a key precursor for polyamides(such as nylon-6,6), polyesters, and polyurethanes.However, its chemical synthesis suffers from high costs, poor sustainability, and environmental risks.To develop an eco-friendly biosynthetic route, this study constructed an 1,6-hexanedial production pathway using adipic acid as the substrate, and enhanced biosynthesis efficiency through targeted gene knockout and fermentation optimization, combined with in vitro catalysis to alleviate product toxicity, thereby improving 1,6-hexanedial accumulation.Results demonstrate that knockout of specific endogenous aldehyde reductase genes combined with fermentation optimization markedly increased yields.The engineered strain achieved 190 mg/L 1,6-hexanedial via in vivo fermentation, representing a 20.3-fold improvement over the parental strain.Subsequent in vitro catalysis elevated production to 295.8 mg/L, corresponding to a 32.2-fold enhancement.This titer stands as the highest reported value in 1,6-hexanedial biosynthesis to date.This work establishes a foundational strategy for biosynthesizing aliphatic dialdehydes.
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